Navegando por Autor "Azevedo, Dina L. O."
Agora exibindo 1 - 2 de 2
- Resultados por página
- Opções de Ordenação
Artigo Adjustments in the time, distance and direction of foraging in dinoponera quadriceps workers(Springer, 2014) Azevedo, Dina L. O.; Medeiros, Jeniffer C.; Araújo, ArriltonWe measured individual decisions regarding the adjustments of time, distance and direction of foraging in Dinoponera quadriceps.We observed two colonies in an area of secondary Atlantic Forest, FLONA-ICMBio, in Northeastern Brazil. The workers were individually marked. We recorded the displacement of workers, their returns to the nest with and without food, the time spent searching for food, maximum and total distance, inter-trip latency and direction of trips. The time spent searching for food, maximum distance and transport velocity did not vary with food size. The previous trip success reduced the latency between foraging trips and increased the percentage of success on the next trip. However, this previous success did not demonstrate a significant variation relative to the time spent searching on the next trip or direction of search. The workers maintained an individual directional fidelity during foraging. The adjustments of these foraging variables under individual control contributed to the efficiency at the colony level. D. quadriceps is compatible with the central place theory and risk sensitivity model of behaviorArtigo Foraging activity rhythms of dinoponera quadriceps (Hymenoptera: formicidae) in its natural environment(Oxford University Press, 2014) Medeiros, Jeniffer; Azevedo, Dina L. O.; Santana, Melquisedec A. D.; Lopes, Talita R. P.; Araújo, ArriltonThis study characterizes the foraging activity of the queenless ant Dinoponera quadriceps (Kempf) (Hymenoptera: Formicidae) in its natural environment by testing the hypotheses that foraging activity presents both daily and seasonal rhythmic variations, and that these rhythms are related to environmental variables. Four colonies of D. quadriceps were observed in an area of secondary Atlantic forest in northeastern Brazil. Data collection was performed over 72 h every three months during an annual cycle. Both daily and seasonal foraging activity rhythms of D. quadriceps colonies were related to environmental factors, but colony differences also explained part of foraging variations. Foraging activity of D. quadriceps colonies was predominantly diurnal independently of season. In the early dry season, the colonies had two activity peaks, one in the morning and another in the afternoon, with a decrease in foraging at midday; however, during the rest of the year, foraging activity was distributed more evenly throughout the daylight hours. The daily rhythm of foraging activity was likely determined by an endogenous circadian rhythm year-round, but in the dry season, temperature and relative humidity also influenced daily foraging activity, with a negative effect of temperature and a positive effect of relative humidity. On a seasonal scale, foraging activity peaked in the early dry season and suddenly declined at the end of this season, increasing again at the late rainy season. The seasonal rhythm of foraging was negatively related to relative humidity and positively related to prey availability